Foodborne illness: A challenge for disease detectives

This column appears in the Nevada Appeal Wednesday health pages. It addresses topics related to the health of our community.

Most of us are familiar with the scenario – after a family reunion, church luncheon, or dinner out, someone begins to show signs and symptoms of foodborne illness. Immediately, people begin to assume that the most recent meal is the culprit. Quickly, speculation spreads about what caused the person to become ill. This is the time when it becomes the epidemiologist’s job to try to track down what really is making the person sick. Epidemiologists are like disease detectives, and they use clues like medical lab tests, food histories, and linking cases of illness together to try to find the cause.

In truth, many foodborne illnesses are not a result of the most recent meal, even though it may seem that way. This tendency to blame the dinner you just finished eating is called “last meal bias” and it can make determining the real cause of illness difficult. It is true that sometimes food poisoning, which is caused by a poison or toxin, and is different from foodborne illness, can happen rapidly. However, most types of foodborne illness, especially those caused by bacteria, take 12 hours or more to make you sick. Some, like E. coli, can even take up to 8 days before you begin to feel ill. It can be difficult to remember what you had to eat 8 days ago. Sometimes we are so busy that we don’t remember what we ate for breakfast. This can make it difficult for the epidemiologists to track down the foods that may be responsible.

Recently, an outbreak of listeriosis caused by Listeria monocytogenes found in cantaloupes has been in the news. Listeriosis is a foodborne illness that takes 3-70 days and has symptoms of fever, muscle aches, nausea, and sometimes diarrhea. Some people are more at risk of getting sick.

The CDC in Atlanta noticed that there were more listeriosis cases than usual, and disease detectives from all over the country worked together to figure out the cause. The investigation is still ongoing nationwide and under review at the CDC. It is important to note though, that locally grown cantaloupes were NOT tied to the outbreak.

If you suspect that you have eaten something that has made you sick, go to the hospital or your physician and get tested. Also, keep an open mind about what may have caused you to become sick. There are disease detectives right here in Carson City that are ready to try to help you track down the realculprit!